I need to buy a disk to add to a customer box. The box (a Dell) is running CentOS 4.4. I dont want to get one that's incompatible with the existing disk(s) (that's happened once already to another customer). How do I determine what kind of disk (SATA, ATA, IDE, etc) is already installed.

Note: 'dmesg' returns a bunch of messages about an 'aacraid' device, and nothing else. Existing disk(s) is/are /dev/sda.

Thanks!

John F

Try hwinfo --disk,lshw or hdparm.Also you can check your /proc directory,for example cat /proc/pci.If that doesn't help try lsdev,lshal,lspci or lsscsi.You can check if you have hwdiag script,if not,it should be in the repos.

sda originally refered to a SCSI drive although SATA drives also are named sda, sdb etc.

If you have access to the PC hit the F2 key when booting up and look at what the BIOS is recognizing. My Dell PC shows 2 SATA drives and a IDE/ATA DVD drive.

You basically have 3 types of disk ATA (aka PATA, IDE), SATA and SCSI. The third is most common in servers. Or pop the cover - ATA has a 40 or 80 wire ribbon data cable attached, SATA has as very small data cable attached.

If it is SCSI you should see a SCSI controller load at boot time. The cables are different although various styles are used. If you have a SCSI system... look at the label on the disk and let us know what model etc.

Ken

p.s. If you are actually running some sort of hardware RAID - that is a little out of my league.